Figure 4: The levels of IL-6 after treatment with 1,25(OH)2D3, MTX, and 1,25(OH)2D3 plus MTX in RA patients. The RA patients’ PBMCs are treated with either anti-CD3/CD28, or 1,25(OH)2D3, MTX at various concentrations, or the combination of 1,25(OH)2D3 and MTX (D2M2 group). The levels of IL-6 were detected and significantly decreased in the groups of 1,25(OH)2D3, MTX, and D2M2 compared to those of the group of anti-CD3/CD28 (). *Mean .